Machine for conditioning false teeth



Nov. 2, 1937. H. P. PFEIFFER 2,097,701

MACHINE FOR CONDITIONING FALSE TEETH Filed Nov. 11, 1955 2 Sheets-Sheet 1 INVENTOR ATTORNEY Nov. 2, 1937. H. P PFEIFFER 2,097,701

I MACHINE FOR CONDITIONING FALSE TEETH Filed Nov. 11, 1935 2 Sheets-Sheet 2 Z6 Z7 1 26 1 a1 15 i 4 INVENTOR I I 1 lyflifyffi'ayffr BY z ATTORNEY Patented Nov. 2, 1937 UNITED STATES- PATENT OFFICE MACHINE FOR CONDITIONING FALSE TEETH Henry P.Pfeiffer, East Orange, N. J.

ApplicationNovem'bei- 11, 1935, Serial No. 49,225

4 Claims.

This invention relatesto-machines for conditioning false teeth, and my improvement is directed particularly tomechanism having means for holding stationary one set of teeth tical movement'in' a horizontal plane, iscaused to impose pressure upon the other set to'induce,

with theaid' of an abrasive, a grinding action 15 between-the sets of teeth for performing the conditioning process; Such pressure may be'imposed by the Weight alone of the upper machine part, or this weight may be supplemented by spring tension.

20 Further'my invention includes the provision'of positive stop means, which may be regulated by micrometer means, to limit the degree towhich the grinding operation may extend;

Still further myinvention includes the provi -25 sion of adjustment meanswhereby the range of the ellipsis may be varied at will, for wider or narrower paths of grinding operation.

Other features and advantages of my invention will hereinafter appear; 30 In thedrawings:-

Figure 1 isa top-plan. view of my improved machine.

Fig. 2 is a side sectional view taken" on the line 2--2 of Fig. 1; showing'sets of teeth'positioned for conditioning.

Fig. 3 is a front sectionalview taken on the line 3-3 of Fig. 2.

Fig. 4 is a detail 'plan' view taken on the line 4'-lof"Fig. 2. 40 Fig. 5 is a detail section taken on the line 5-5 of Fi 2.

Fig. 6 is a sid'e' sectional detail showing the sets of teeth as mounted'with plaster of Paris within the machine, and 45 Fig. 7 is a perspective view showing the sets of teeth as adjusted in occlusive relation and set with wax prior'to placement in the machine.

In carrying out myinvention l'provide a plate' or table I, mounted as by legs 2 upon a base 3 591 and adaptedon-its upper surface to support the as a bed: for teeth which are to be. conditioned.

Posts I secured'upon table I at one end thereof, and connected by a tie rod 8; each have a bearing head 9 which contains a socket composed of upper and lower opposed channels l0, 5 I I. These channels are each concaved in crosssection and adapted to revolubly' and slidably" contain between them spherical members I2 which respectively are pierced and slidably mounted on'bearing end's I3 of a shaft [4 that 10 fixedly carries an arm l5- transversely disposed with'respect to saidshaft. Said arm [5, which is given a curve lfi'to elevate it. suitably for a purpose to be referred to hereinafter, is'adapted to extend forwardlyfrom shaft Hand is' of substantial thickness to accord it a desired degree of weight.

S'ecured'to the underside ofarm l5 is'adisk 11, positioned to be in opposed'rel'ation'to disk' Eand having l'odg'ement holes 18 for plasterof 20 Paris.

Arm l5, towardits forwardend; has a'vertical boss I9 whichis pierced for the slidablerecep tion of a rod 20", whose lower end isprovidedwith' a ball-like memberZl, which'isadapted'toen- 5 gagein a cup-shaped depression 22"formedin nut-like block 23'. Said' block 23 is engaged at its under side by a screw'2 l* which is centered upon'and carries atransversely'disposed cylindrical member Z5that" is adapted to slidably engage a groove 26 provided therefor in a mount 2l'which is revolubly supported by a fixed bearing member 28" secured'tothe table I. A shaft 29' extended from 'mount 21 through bearing member 28 carries a worm gear'wheel 30 below table i. The gear 30 meshes with a worm shaft 3ith'at is journalled in bearings SZ'depending from plate I, said shaft carrying a pulley 33 for power driving. The ratio of worm to the gear is such that the relatively high speed of the shaft 40 is translated through said gear to a suitably low speed for shaft 29 and mount 21;

The purposeof mounting arm 15 in the bearing heads 9 in the manner described is that the shaft 20 carried by the forward portion of said arm may be capable with said arm of describing an ellipsis While power is applied to drive shaft 3|; Obviously, if screw 24 is centered in mount 21, to be in axial alignment with the axis of shaft 29 the rotation of said shaft can have no 6 effectupon shaft 29 which will under such condition merely remain stationary during such rotation. But if screw 24 be axially offset, ever so slightly, the effect is to sway shaft 20 and hence arm i5, causing a movement thereof in an orbit human lower jaw upon the upper jaw.

Just according to the extent of shifting mem-- ber 25 axially so is the orbit or elliptical path varied in extent for the shaft 20 and consequently for the arm l5, with the degree of adjustment determined by tightening nut member 23 upon screw 24.

Since the arm l5 carries one set of teeth in opposed relation to the other fixed set, as will be hereinafter described, so the orbital movement given arm l5 causes the set of teeth movable therewith to have a grinding action of an elliptical nature upon said stationary set of teeth.

The rod or shaft 20, which I also term a pole, is the element which provides, in the path of the ellipsis described thereby, the pull and push that performs the function of reproducing the path of curvature between the sets of teeth in similitude to the natural masticatory movement of the In preparing the sets of false teeth for conditioning they are placed together in occlusive relation as shown in Fig. 7 and are held in that relation with wax in the manner well known in this art and then in the manner also well understoodare mounted respectively in plaster of Paris upon the disks 5, IT. The depths of the plaster beds determining the extent of space separating arm 15 from the table.

When the false teeth are set in this relation the wax holding the sets together is removed and the" shaft 20 is to be adjusted in its relation to arm l5 so that the ball 2| at the end of said shaft is held clearingly above the base of socket 22. This means that the upper set of teeth, under the full weight of arm I5, is supported upon the lower set, and the amount of clearance separating ball 2| from the base of socket 22 represents, in the degree of drop permitted for shaft 20, the extent to which the grinding operation between the sets of teeth can be performed.

7 It is to be understood that the sets of teeth, in

their occlusive relation and as set in the apparatus, are placed exactly toward the axis of shaft 29, which axis is immovable, so that the elliptical movement that ensues in the operation of the machine simulates the planetary motion of the lower jaw and thus communicates a natural grinding action between the upper and lower sets of teeth.

In providing means of axial adjustment for shaft 20 relatively to arm l5 and the rest position of the upper set of teeth upon the lower set, I employ these instrumentalitiesr Seated in a recess 34 in the top of boss I9 is a collar 35 forming the base of an interiorly threaded sleeve 36, which sleeve is screwed upon shaft 29. A plate 31,.secured to boss l9, and orificed for the reception of sleeve 36, engages collar 35 to revolubly retain sleeve 36, and a knurled thumb nut 38, fitting over shaft 20 is connected to sleeve 36 as by set screw 39. Thus, upon rotating thumb nut 38 shaft 20 may be raised or lowered through boss l9. When shaft 20 is shifted to a desired position it is to be set therein by means of a set screw 40 entered through boss l9 and impinging upon the shaft 20 for that purpose.

The thumb nut 38 may be provided with numeral indications to register for example degrees of vertical adjustment for shaft 20 for the predetermined regulation of the depth to which the teeth are to be ground.

To supplement the pressure imposed by the weight of arm l5 in the teeth grinding action I may add the tension of a spring 4| which connects said arm to the table.

Variations within the spirit and scope of my invention are equally comprehended by the foregoing disclosure.

I claim:-

1. A machine for conditioning false teeth comprising a table, means thereon to fixedly support a set of false teeth, bearing means carried by said table at one end thereof, an arm loosely journalled at one end in said bearing means, said arm supporting a companion set of false teeth in occlusive, gravity pressure relation to said fixedly supported set, a revoluble member, having a horizontal groove, mounted on said table, means to rotate said member, an axially adjustable, cylindrical member carrying a centered upstanding screw, a nut-like block having a cup-shaped depression in its upper surface, and a pole having a. ball-like end revolubly fitting said depression, said pole, according to the degree of axial adjustment of said cylindrical member, communicating movement through an ellipsis to said pole and thence to said arm and the set of teeth carried thereby.

2. The subject matter of claim 1 characterized by the provision of tensional means, connected to said arm and said table, supplementary to grayity, in applying pressure of one set of teeth upon the companion set for the grinding operation.

3. A machine for conditioning false teeth embodying means to fixedly support a set of false teeth, an arm supporting a companion set of false teeth in occlusive, gravity pressure relation to said fixedly supported set, bearing means loosely journalling one end of said arm, a revoluble member having a groove, an adjustable element mounted in said groove, a block carried by said adjustable element and a pole having its lower end projecting into said block, said pole, according to thedegree of adjustment of said adjustable element, communicating movement to said supporting arm and the set of teeth carried thereby.

4. A machine for conditioning false teeth embodying means to fixedly support a set of false teeth, an arm supporting a companion set of false teeth in occlusive, gravity pressure relation to said fixedly supported set, bearing means loosely journalling one end of said arm, a revoluble member having a horizontal groove, an axially adjustable element mounted in said groove and having a centered upstanding screw, a block carried by said screw, and a pole revolubly carried by said block, said pole, according to the degree of adjustment of said adjustable element, communicating movement through an ellipsis to said pole and thence to said supporting arm and the s f teeth arried thereby.

. HENRY P. PFEIFFER. 

